The University of Southampton
University of Southampton Institutional Repository

Development and application of a self-referencing glucose microsensor for the measurement of glucose consumption by pancreatic ?-cells

Development and application of a self-referencing glucose microsensor for the measurement of glucose consumption by pancreatic ?-cells
Development and application of a self-referencing glucose microsensor for the measurement of glucose consumption by pancreatic ?-cells
Glucose gradients generated by an artificial source and ?-cells were measured using an enzyme-based glucose microsensor, 8-?m tip diameter, as a self-referencing electrode. The technique is based on a difference measurement between two locations in a gradient and thus allows us to obtain real-time flux values with minimal impact of sensor drift or noise. Flux values were derived by incorporation of the measured differential current into Fick's first equation. In an artificial glucose gradient, a flux detection limit of 8.2 ± 0.4 pmol·cm-2·s-1 (mean ± SEM, n = 7) with a sensor sensitivity of 7.0 ± 0.4 pA/mM (mean ± SEM, n = 16) was demonstrated. Under biological conditions, the glucose sensor showed no oxygen dependence with 5 mM glucose in the bulk medium. The addition of catalase to the bulk medium was shown to ameliorate surface-dependent flux distortion close to specimens, suggesting an underlying local accumulation of hydrogen peroxide. Glucose flux from ?-cell clusters, measured in the presence of 5 mM glucose, was 61.7 ± 9.5 fmol·nL-1·s-1 (mean ± SEM, n = 9) and could be pharmacologically modulated. Glucose consumption in response to FCCP (1 ?M) transiently increased, subsequently decreasing to below basal by 93 ± 16 and 56 ± 6%, respectively (mean ± SEM, n = 5). Consumption was decreased after the application of 10 ?M rotenone by 74 ± 5% (mean ± SEM, n = 4). These results demonstrate that an enzyme-based amperometric microsensor can be applied in the self-referencing mode. Further, in obtaining glucose flux measurements from small clusters of cells, these are the first recordings of the real-time dynamic of glucose movements in a biological microenvironment.
0003-2700
3759-3767
Jung, Sung-Kwon
9b10457b-933f-4247-a75a-62320f744dc7
Trimarchi, James R.
dc15c269-2b07-41fb-b3e5-a9ac457c7994
Sanger, Richard H.
eb4dde62-3c95-4a17-ac97-aba2a2ae5baf
Smith, Peter J. S.
003de469-9420-4f12-8f0e-8e8d76d28d6c
Jung, Sung-Kwon
9b10457b-933f-4247-a75a-62320f744dc7
Trimarchi, James R.
dc15c269-2b07-41fb-b3e5-a9ac457c7994
Sanger, Richard H.
eb4dde62-3c95-4a17-ac97-aba2a2ae5baf
Smith, Peter J. S.
003de469-9420-4f12-8f0e-8e8d76d28d6c

Jung, Sung-Kwon, Trimarchi, James R., Sanger, Richard H. and Smith, Peter J. S. (2001) Development and application of a self-referencing glucose microsensor for the measurement of glucose consumption by pancreatic ?-cells. Analytical Chemistry, 73 (15), 3759-3767. (doi:10.1021/ac010247u).

Record type: Article

Abstract

Glucose gradients generated by an artificial source and ?-cells were measured using an enzyme-based glucose microsensor, 8-?m tip diameter, as a self-referencing electrode. The technique is based on a difference measurement between two locations in a gradient and thus allows us to obtain real-time flux values with minimal impact of sensor drift or noise. Flux values were derived by incorporation of the measured differential current into Fick's first equation. In an artificial glucose gradient, a flux detection limit of 8.2 ± 0.4 pmol·cm-2·s-1 (mean ± SEM, n = 7) with a sensor sensitivity of 7.0 ± 0.4 pA/mM (mean ± SEM, n = 16) was demonstrated. Under biological conditions, the glucose sensor showed no oxygen dependence with 5 mM glucose in the bulk medium. The addition of catalase to the bulk medium was shown to ameliorate surface-dependent flux distortion close to specimens, suggesting an underlying local accumulation of hydrogen peroxide. Glucose flux from ?-cell clusters, measured in the presence of 5 mM glucose, was 61.7 ± 9.5 fmol·nL-1·s-1 (mean ± SEM, n = 9) and could be pharmacologically modulated. Glucose consumption in response to FCCP (1 ?M) transiently increased, subsequently decreasing to below basal by 93 ± 16 and 56 ± 6%, respectively (mean ± SEM, n = 5). Consumption was decreased after the application of 10 ?M rotenone by 74 ± 5% (mean ± SEM, n = 4). These results demonstrate that an enzyme-based amperometric microsensor can be applied in the self-referencing mode. Further, in obtaining glucose flux measurements from small clusters of cells, these are the first recordings of the real-time dynamic of glucose movements in a biological microenvironment.

Text
ac010247u.pdf - Version of Record
Download (167kB)

More information

Published date: June 2001
Organisations: University of Southampton

Identifiers

Local EPrints ID: 188847
URI: http://eprints.soton.ac.uk/id/eprint/188847
ISSN: 0003-2700
PURE UUID: bd3df1bc-8612-447f-bc1d-0476a6774381
ORCID for Peter J. S. Smith: ORCID iD orcid.org/0000-0003-4400-6853

Catalogue record

Date deposited: 03 Jun 2011 13:18
Last modified: 15 Mar 2024 03:38

Export record

Altmetrics

Contributors

Author: Sung-Kwon Jung
Author: James R. Trimarchi
Author: Richard H. Sanger

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×